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Bob, I would agree completely. A great and civil discussion w/ many views and opinions. No boasting is assumed, only the benifit of one who has experianced something that many other [myself included] could only dream of.
I'd noted that you felt more comfortable in the jets and from there [knowing the Stall issues w/ the F16] was just looking at the comparison of stall behaviour. As I understand it if you stall the F16 to a point [w/ it's Aft CG] it becomes fairly difficult to recover. I've read accounts of such 'departures' happening and the hair raising exeriance of trying to recover. The assumption is that some of these accounts would be w/ some poetic license, but the underlying premise is that they CAN be a bear if stalled incorrectly. These airframes are certainly a long ways from the Lancair family. I fly an aircraft corporatly that has [basically] the same performance spec's [speed] as a 'factory' IV [285knt @ 240] however I can carry a few more people than a IV, on the lower end of the spectrum it stalls down in the 85knt range depending on weights etc. So one can have their cake and eat it if one really wants to. [ie; not every plane that 'performs' in cruis
e has to be a dangerous slow speed flyer; or said another way, not every plane that is safe/docile in the slow speed range has to be a dog in the high speed range]
The subject line above [not sure where it came from] is a bit of a mis-nomer in that I don't think there is any FIXING that needs to be done w/ the IV. I was talking w/ John H. offline about this, I think there is some that think I'm pushing for a change in the wings or tail or whatever to make the airframe safer. Maybe others are pushing this point, it certainly isn't my basis. I think there is some TUNING that could be done to improve the slow flight [approach to stall only] areas of the envelope. Primarily I'm looking at approach to stall buffet and wing drop. Both of these should be able to be tuned w/ the simple use of stall strips or in the worst case [really worst case, which I think would be rare] the resetting of the wing incidence due to builder error etc. At best, the addition of a simple stall strip or control surface rigging should give the onset buffet as well as elliminate wing drop in the approach to stall and initial recovery areas.
Both of these steps should be relatively easy to impliment [cost and time wise].
You'd noted that you slowed to onset [I assume this to mean pre-stall buffet] during your pre-buy and then recovered. THIS is all I'm promoting as a point of reference in flight testing. There are many [if I'm reading these emails correctly] who have NEVER done that very step in flight testing their airframes. In no way am I advocating using any Lancair for aerobatics or advanced training [stall/spin] of any sort. Nor would it need to be something that one should be doing on a daily or even weekly basis, every 6mo or a year maybe, but only as a step in recurrency training. I agree that these planes are built for 'going places' and are well suited in that area of the envelope. I just wish more would do the 'approach to stall' tests during their flight tests, rather than "slow down to a number that looks slow and then speed up
". The problem w/ doing the approach to stall is that in some planes [as I understand it] there is no warning to the stall, it just happens and more often than not, it includes a wing drop. Hence my pondering of a 'group shared' spin chute for testing.
I think there is a bit of a incorrect belief that all of these kit planes are geometrically the same and will perform the same because they came from the same molds. From my experiance and what I've read here, this is far from the truth. Each airframe is an individual, they each have their own querks and issues. Having to re-tune them aerodynamically is something that should be expected as a nesc step in flight testing. From what I've been reading there is a large number of owners who do-not-do this step but rather leave anything that would be 'aerodynamics' to the assumption that 'it will be right' [or 'alright'], I believe this to be a larger part of this 'don't investigate the low speed range' mindset. I believe it is our responsibility to work w/ the aerodynamics and tune the airframe, to avoid this step [dealing w/ the aerodynamics] because it is not our expertise is the same as 'not building an airplane because it should be done by perfessionals', we know we can build t
hese airplanes, we can also tune them to behave.
I can't speak for 737 pilots but I can tell you in my corporate plane that I drive, I have [and am required to regularly] demonstrate approach to stall in the actual airplane while doing recurrency training. In the certified airframe its not a big deal, you slow down look for and find the needed indicators and recover. This isn't happening in the larger community of Lancair drivers which is the root of my concern.
Anyway, thanks for the great response, it's wonderful when these discussions can be as light and easy as this has. There will be never be a final conclusion to the question, at least not until the last Lancair stops flying and that could be a while. Until then, it will keep coming back to be discussed and then left for time.
At the end of it all, fly safe and come home alive. It's all that matters.
Best Regards
Jarrett Johnson
235/320 55% and holding
> Jarrett
> I think this is a good discussion, and I'm not trying to boast
> about my fortunate flying career or be pretentious in any way.
> Just being direct.
>
>
> First of all, let's define the difference between a stall and "out
> of control". The F-16 flight control computer was designed to not
> allow an AOA (in positive pitch) of above 25 degrees no matter
> what the pilot asks for with the stick. At that AOA limit, the
> wing is not flying anymore, but the plane handles just fine (
> usually in a big sink rate unless you are low with the AB cookin).
> We used this AOA to slow down and get nose authority for
> fighting. Out of control is a different animal all together. If
> you overshoot the roll/pitch/yaw limiters and truly are not in
> control of the nose, it's an emergency procedure. You really have
> to try hard to make this happen, but it does happen every so
> often. So it is a misconception to say that the F-16 has "super
> poor" stall recovery ability. In fact, a select few of us each
> year get to go to Edwards and intentionally put an F16 out of
> control repeatedly, and practice recovering from it. As long as
> you have some altitude and the CG of the airplane is not
> intentionally mishandled, you can recover every time with the
> proper technique. Bottom line, It's a very poor comparison to
> the 4P.
>
> Additionally, I didn't say I was more comfortable in a fighter, I
> said the 4P is harder to land, which it is. The F16 is still at
> flying speed when you land, so its easy to handle near the runway
> ( long story offline about F16 landing technique). The HUGE wing
> on the F22 makes landing a piece of cake. My very first landing
> in the F22 was better than my very best landing in the 4P, because
> there is so much more design differences (leading edge flaps, HUD,
> digital flight control computer, 70,000 pounds of thrust if you
> need it, etc) that aide landing.
>
> I will say it again, the 4p doesn't need fixed (the strake for a
> turbine 4P excluded I guess). In my opinion, what needs fixed are
> some pilots attitude toward the airplane. Maybe the fact that
> this is an experimental aircraft gives some people the idea that
> they can mess with it. I think there is a big difference on
> whether you have sunshades in the cockpit or change the baggage
> door locking mechanism vs. fooling with the aero design. There
> had to be a thousand tradeoffs in the design process for this
> airplane. I for one think Lance made the right choices for a
> plane that has very unique performance characteristics. Takeoff,
> Go fast, cruise in a straight line a far distance, land, Period.
> Faster and more efficient than anything else like it in the world.
> It wasn't designed to fly slow, do acro, stalls/spins, or
> anything of the kind. If you "fixed" all of the perceived
> problems with the 4P, you would end up with a Cessna or Bonanza.
> You can't have it both ways. Don't think that other airplanes
> ability to do these things safely is a reason that you should try
> it in a 4P. If you can't stay ahead of the airplane in all
> circumstances enough to avoid a stall, or if you must go practice
> a stall for your own reasons, then don't get a 4P. Get a Cirrus
> so you can ride a parachute if you mess up.
>
> Does a 737 or 747 need fixed because it can't stall and recover
> easily? No, and airline pilots don't go there either, except in
> the simulator. It was designed for cruise efficiency. Same story
> with the 4P,and we don't have a simulator to practice in either!
>
> I'm comfortable with my family in the airplane because I know the
> limits of the airplane. I know it won't act good in a stall so
> I'm not going there. I'm not saying you should not learn those
> skills in another airplane that was designed for it, but I am
> saying that outside of the testing/certification process on this
> airplane it is a bad idea, no matter what your skill level is. I
> accept the fact that my desire for high speed efficient cruising
> necessitates a high landing speed and poor high AOA performance.
> When I was checked out in my aircraft, we slowed down to the
> onset for a demonstration of the aircraft performance, with plenty
> of altitude below us. Now I know where the limit is, and to never
> go there. 4P pilots should not either, in my opinion.
>
>
> On Jun 27, 2011, at 11:16 AM, H & J Johnson
> <hjjohnson@sasktel.net> wrote:
>
> > I swore I was just going to sit on my hands but.... darn-it I
> can't.
> >
> > Bob your saying your more comfortable in a fighter [which has
> known for its SUPER POOR stall recovery ability] in slow flight
> than you are in the IV? I can't comment on the F22 as I never
> learned much about what it can or can't do in the stall. I can
> imagine w/ the vectored thrust that it's never going to be an
> issue unless your dead stick [at which time the plane would have
> to fend for itself while you pulled the 'handle', I'm sure] but
> the F16 has been known [since it was built] that it has NEARLY
> unrecoverble in a stall. If you hit 10000' and your not recovered,
> just pull the handle. I've read accounts of test pilots who
> stalled them and it took 15000+ft to recover and then just barely
> before the hard-deck. As I understand it, to recover you need to
> use stick movement in the direction of the oscillations [rocking
> the plane in pitch to get it to 'unstall' at the apex of one of
> the down pitch oscillations]. So it's established, the F16 is not
> one to be stalled, infact I think there is a 'down pitch' command
> [built into the control software for the flight controls] that
> comes into play if the plane gets too slow. The only way to
> actually stall the airframe is to override that 'down pitch command'.
> >
> > So your ok flying in slow flight w/ that type of plane but not
> in a IV, doesn't that speak to the need for more testing of the
> airframe to 'get comfortable'? I have no doubts in your skills,
> zero. You are as good a qualified pilot as we're going to find for
> the 'hands on, non-straight/level' stuff yet you don't want to
> explore the lower end of the envelope on the plane you carry
> family members in. Granted the IV doesn't have a 'seat' but it
> could have a spin chute! I understand that the F16's and 22's
> have had extensive test flying and their pilots extensive training
> and this is why their pilots are ok w/ slow flight, this is
> exactly what the IV needs [and the 300 series also] to 'tame' them.
> >
> > Also it was mentioned about the F86 demonstration.... All I can
> say is 'exactly', he stayed inside the envelope, he also knew
> where the envelope was, what the limitations w/ the airframe were
> and where he could push it and where he couldn't. He was also
> flying an airframe that was well tested and it's deficency's
> known. He obviously was also a very skilled pilot. Would a person
> DARE try this in a Lancair? I'd hope not. That said, if you knew
> the airframe inside and out and it's limitations and how it
> behaved [was tamed??] in extreeme edges of the envelope then maybe
> a person skilled enough could do something similar [no that's not
> an endorsement on my part to try it in any form].
> >
> > Bob Hoover showed a similar type of flying w/ his Shrike
> Commander back in the day in a plane that was never intended to be
> flown thus. The bottom line of all this [as I see it] is the
> 'amazing' flying that has been discussed always occurs in an
> airframe that is well tested and adjusted, by skilled pilots who
> are well trained. If we were to apply those same criteria to the
> IV and 300's [ok lets just say 'Lancairs'] then there could/would
> be the same level of confidence in those airframes also.
> >
> > Ok onto another endless topic... FORD or Chevy? [a topic as
> likely to be solved as this 'To Stall or Not to Stall' topic :) ]
> [or how about MAC or PC?]
> >
> > Jarrett Johnson [ok back to sitting on my hand again..]
> > 235/320 55% and holding
> >
> >
> > > Pile on to the fighter comment:
> > >
> > > I flew F16s for 18 years and now fly the F-22. Both of those
> > > planes are easier to land than my IV-P. I have flown a lot of
> > > slow speed stuff in those planes, and I don't Intend to
> explore
> > > the stall characteristics of my plane, ever. If you are
> learning
> > > to fly, then yes, do so in a plane than can stall and was
> designed
> > > for it. Do all of that, get 1000 hours, and THEN get a IV-P,
> and
> > > quality training on how to fly it. Personally I get weary of
> the
> > > repeated " You need to see how it stalls if it ever happens"
> > > attitude. If you stay ahead of the airplane and don't take it
> > > where it doesn't need to be, you will never be there. It's
> never
> > > going to happen in this plane unless it's unintentional, and
> > > unless you are 10,000' up you are going to hit the ground and
> it
> > > isn't going to be pretty- period! The IV-P was designed to
> fly
> > > fast and efficient over long distance. Not to do acrobatics,
> > > stalls, anything else. It doesn't need to be fixed, it does
> > > exactly what it was intended to do! And pilots who wanna fix
> the
> > > IV-P or stall it should fly something else ( in my opinion).
> > >
> > > Bob R
> > >
> > >
> > >
> > > On Jun 24, 2011, at 10:02 PM, John Hafen <j.hafen@comcast.net>
> wrote:
> > >
> > > > One has to choose between stall strips and a heated leading
> edge.
> > > >
> > > > For me personally, stall strips would be more applicable for
> my
> > > Cub, which doesn't need them at all. And I have been in
> > > inadvertent icing conditions in the IVP and watched the ice
> curl
> > > up like potato chips and blow away. I'll keep the heated
> leading
> > > edge, thank you, rather than a stall strip that I would never
> use.
> > > >
> > > > And as far as a larger tail???
> > > > A. Who is going to spend the additional money to make
> their
> > > IVP look stupid?
> > > > B. The IVP is tail heavy already -- no one wants to load
> > > extra weight aft of the CG.
> > > > C. Challenged pilots should perhaps fly a different
> plane.
> > > >
> > > > I love the IVP the way it is. I have never crashed and
> died. I
> > > understand the envelope, and like it;)
> > > >
> > > > John
> > > >
> > > > (On military pilots and "training" to fly unstable air craft
> --
> > > I don't think you are accurate on this one. The F-16 is so
> > > unstable that it requires 20+ inputs per second to maintain
> > > straight and level flight. It is computerized. No human
> being on
> > > earth, no matter how highly trained, can manually fly an F-16
> > > straight and level. The "fly by wire" F-16 is way easier to
> fly
> > > than my IVP. The original side stick didn't move at all, but
> > > responded to pressure. Pilots hated it so it was redesigned
> to
> > > move slightly. And the pilots wishes to go a computer that
> > > controls the flight surfaces. There is no direct manual
> > > connection from the stick to the flight control surfaces.
> Even in
> > > the old F4, the flight control "feel" was artificial -- based
> on
> > > springs, as the hydraulic system supplied 3,000 psi to the
> flight
> > > control surfaces, which came in really handy over about mach
> 1.1.
> > > You don't need a million dollars worth of training to fly a
> IVP
> > > safely. HPAT, yes.)
> > > >
> > > > On Jun 24, 2011, at 11:24 AM, Wolfgang wrote:
> > > >
> > > > Military aircraft are unstable to allow better agility.
> > > > Military pilots get over a million dollars worth of training
> > > each to be able to handle their "unstable" aircraft.
> > > >
> > > > I don't see that happening for IVP drivers.
> > > >
> > > > There are a couple of things that can be done that don't
> > > adversely affect performance or handling.
> > > > Stall strips and larger tail feathers come to mind.
> > > >
> > > > Wolfgang
> > > >
> > > > From: John Hafen <j.hafen@comcast.net>
> > > > Sender: <marv@lancaironline.net>
> > > > Subject: Airplane needs to be "fixed," Stall Speeds, Wing
> Cuffs,
> > > Vortex Generators for L...
> > > > Date: Fri, 24 Jun 2011 06:05:59 -0400
> > > > To: lml@lancaironline.net
> > > > Wolfgang states: "If the airframe can't get back in the
> > > envelope, then the airframe needs to be fixed."
> > > >
> > > > There are lots of historical examples to the contrary, like
> the
> > > F4 Phantom. Once in a flat spin, the plane was unrecoverable
> from
> > > any altitude. "Stick Forward, Ailerons and Rudder Neutral, If
> not
> > > Recovered, Maintain Full Forward Stick and Deploy Drag Shoot"
> were
> > > not enough.
> > > >
> > > > Yet the F4 was the work horse fighter for the Navy, Air
> Force,
> > > Marines, and hosts of allies for decades. And it was fast,
> over
> > > Mach II.
> > > >
> > > > Yet, you stayed far far away from "departing" -- high angle
> of
> > > attack, stick one way and the rudder the other.....
> > > >
> > > > Most advanced stalls in IVP are recoverable, given 10,000
> feet
> > > or so.
> > > >
> > > > But unlike the F4, most of our IVPs are not equipped with
> Martin-
> > > Baker ejection seats.
> > > >
> > > > The F4 never got fixed. The IVP got "fixed." It's called
> the
> > > "ES," with larger differently shaped wings and fixed gear,
> that
> > > became the Columbia/Cessna.
> > > >
> > > > The "fix" was a series of tradeoffs that IMHO made it a less
> > > desirable plane -- slower, fixed gear, non-pressurized.
> > > >
> > > > I'll happily keep the un-fixed version of the IVP myself,
> thank
> > > you.
> > > >
> > > > John Hafen
> > > >
> > > >
> > > >
> > > >
> > > > On Jun 23, 2011, at 9:11 AM, Wolfgang wrote:
> > > >
> > > > I, for one, want to be able to recover from an "adverse"
> > > condition should I ever find myself in one.
> > > > Knowing where the edges of the envelope are and how to get
> beck
> > > in the envelope should be required.
> > > > If the airframe can't get back in the envelope, then the
> > > airframe needs to be fixed.
> > > >
> > > > Wolfgang
> > > > ----- Original Message -----
> > > > From: Karen Farnsworth
> > > > To: lml@lancaironline.net
> > > > Sent: Wednesday, June 22, 2011 2:12 PM
> > > > Subject: RE: [LML] Re: Stall Speeds, Wing Cuffs, Vortex
> > > Generators for L...
> > > >
> > > > David,
> > > >
> > > >
> > > > I have no problem with anyone who wants to explore the
> > > “envelope” of his/her airplane. However, I take great
> exception to
> > > you grounding me because I might choose to not get as near to
> the
> > > edge as you.
> > > >
> > > >
> > > > Lynn Farnsworth
> > > >
> > > > Super Legacy #235
> > > >
> > > > TSIO-550 Powered
> > > >
> > > > Reno Race #44
> > > >
> > > > Mmo .6
> > > >
> > > >
> > > > I agree 100% also.
> > > >
> > > > If you don’t know what the incipient stall feels like in the
> > > stick and the airframe you should not be flying the Legacy or
> > > 320’s.
> > > >
> > > > (Not knowing this is the single biggest killer of Lancair
> pilots.)
> > > >
> > > >
> > > > David T.
> > > >
> > > > Legacy
> > > >
> > > >
> > > >
> > >
> > --
> > For archives and unsub
> http://mail.lancaironline.net:81/lists/lml/List.html
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